dsh-token-ledger: A Transparent Token Ledger for DeepSeek Harness

`dsh-token-ledger` is a token-counting verification plugin designed for DeepSeek Harness (DSH). It folds persistent session logs into aggregate token totals, ensuring restart safety. Core features include an audit command (validating data consistency through diff), billing report generation (with CSV/JSON export support), and a lightweight, zero-dependency architecture. The tool is suitable for scenarios requiring defensive validation of token statistics, audit logs, or exportable billing reports, ensuring data accuracy by recomputing from raw logs.